Cartridge fuse connector and connecting block



Dec. 23, 1969 J. SEAGRAVE ET AL 3,486,154

CARTRIDGE FUSE CONNECTOR AND CONNECTING BLOCK Filed Oct. ('99, 1967 United States Patent r 3,486,154 CARTRIDGE FUSE CONNECTOR AND CONNECTING BLOCK James Seagrave and Norman Welburn, Bushey Heath, Hertshire, England, assignors to AMP Incorporated, Harrisburg, Pa.

Filed Oct. 30, 1967, Ser. No. 679,030 Claims priority, application Great Britain, Nov. 15, 1966, 51.030/ 66 Int. Cl. H01h 85/02, 85/46 U.S. Cl. 337188 7 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a fuse connector and is particularly concerned with the provision of a connector for receiving conventional cartridge fuses or strip fuses such as printed circuit fuses as alternatives.

Conventional fuse connectors for cartridge fuses generally comprise a block of insulating material carrying spaced contacts with receptacle portions for receiving end caps of a cartridge fuse. Insertion of a cartridge fuse between a pair of contacts by engaging the fuse end caps in the respective receptacle portions connects the fuse link of the cartridge between the contacts.

Such fuse connectors are frequently used in cars for protecting the electrical wiring.

It has been proposed to utilize printed circuit fuses or strip fuses in place of the conventional cartridge fuses to save expense and also to reduce the necessary size of the connector. A printed circuit or strip fuse comprises a strip of insulating material or card formed on a face with a strip or printed conductor having contact portions at opposite ends with an intermediate portion of reduced width. The intermediate portion is adapted to fuse on passage of a predetermined current. To facilitate fusing of the intermediate portion to give a clean break in the circuit, the intermediate portion may be arranged to bridge an aperture in the strip of insulating material or card.

In view of the requirement to replace the cartridge fuses with strip or printed circuit fuse elements and the current general use of cartridge fuses there is a need for a connector which will operate with either type of fuse.

A fuse connector according to the present invention comprises a block of insulating material formed with a cavity for receiving a cartridge fuse, a pair of contacts mounted in the block having receptacle portions disposed in the cavity for receiving respective ends of the cartridge fuse, the block being formed with a slot for slidably receiving a surface of the strip or printed circuit fuse element, portions of the contacts being exposed within the slot for frictionally engaging a surface of the strip or printed circuit fuse element.

In one embodiment end portions of the fuse element are arranged to be gripped between the portion of the contacts exposed within the slot and an opposite side of the slot.

A block may be formed with a plurality of cavities arranged side by side for receiving respective cartridge fuses. In such arrangement the block may be formed with a slot extending through the block and communicating 3,486,154 Patented Dec. 23, 1969 with all of the cavities whereby a printed circuit card carrying a plurality of spaced parallel fuse elements may be inserted into the slot to position the elements in respective cavities in one operation. In such arrangement the card may carry a duplicate set of fuses laterally displaced from the first set so that in the event of fuse failure the card may be moved laterally to position a fresh set of fuse elements between the contact pairs.

In addition, short slots may be formed adjacent each contact, communicating with the slot extending through the block so that individual printed circuit or strip fuses may be inserted laterally of the main slot through the short slots.

Other objects and attainments of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which there is shown and described an illustrative embodiment of the invention; it is to be understood, however, that this embodiment is not intended to be exhaustive nor limiting of the invention but is given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify it in various for-ms, each as may be best suited to the conditions of a particular use.

The invention will now be described by Way of example, with reference to the accompanying partly diagrammatic drawings, in which:

FIGURE 1 is a perspective partially fragmented view of a fuse connector, and

FIGURE 2 is a fragmentary view of part of the connector of FIGURE 1 with an alternative printed circuit fuse element in position.

In FIGURE 1 a flat slab-like block 1 of insulating material is formed with a series of apertures 2 defining cavities for receiving respective cartridge fuses CF. The block is formed along upper and lower edges with a row of contact receiving passageways 3 communicating with respective apertures 2. Each passageway 3 is arranged to receive a contact 4 having one but preferably a pair of tabs 5 projecting externally of the block and a fuse-cap receptacle portion 6 disposed within the associated aperture 2. The contact 4 at a transition section between the tabs 5 and receptacle 6 is formed with a latch ear 4a for latching engagement with a shoulder 3 to latch it in the associated passageway.

Each passageway 3 is of generally H-shape configuration with a contact secured in one side limb of the H and the other side limb of the H defining a passageway slot for reception of a printed circuit fuse element 7. The fuse element 7 is slidable into the slots defined by the passageways to be clamped between ends 8 of the side arms of the contact receptacle portions 6 and an opposite site of the slot defined by the side limb of the passageway 3. T 0 this end the ends 8 of the receptacle arms are turned out to define bearing surface engaging the adjacent face of the fuse element 7. Flexure of the arms of the receptacle portion 6 provides resilient contact pressure against the fuse element 7 which is formed with a conductive strip on opposite sides so that it is reversible. The conductive strips are narrow over a middle portion but at each end are of increased width equal to the width of the insulating card of the fuse element 7 to provide an extended area for frictional contact by the ends of arms 8 of the receptacles 6.

An elongated slot 9 extends through the block 1 and communicates with all of the cavities 2 opposite the sides for receiving the fuse elements 7. As seen in FIGURE 2, each receptacle portion 6 is formed with a projecting raised rib 10 at its rear which is disposed Within the crosssection of slot 9. An elongated printed circuit card 11 is slidably disposed in slot 9 and at opposite edge portions is resiliently clamped between the contact projections 10 and an opposite side of the slot 9.

The card 11 is formed at spaced intervals with printed circuit fuse elements 12 which at opposite ends are engaged by projections 10 of respective contacts. As shown in dotted lines, a set of fuse elements 13 is laterally offset from elements 12 so that elements 13 alternate with elements 12. By lateral sliding movement of the card 11 along slot 9, the set of elements may be arranged to interconnect the pairs of contacts at the cavities 2 in place of elements 12. Thus, in event of failure of any fuse element 12, the elements may be replaced by fuse elements 13 merely by repositioning the card 11. If desired, the card 11 may be formed with duplicate sets of fuse elements on opposite sides.

It will, therefore, be appreciated that the aforementioned and other desirable objects have been achieved; however, it should be emphasized that the particular embodiment of the invention, which is shown and described herein, is intended as merely illustrative and not as restrictive of the invention.

The invention is claimed in accordance with the following:

1. A fuse connector comprising a block of insulating material provided with a cavity for receiving a cartridge fuse, a pair of contacts mounted in the block having receptacle portions disposed in the cavity for receiving respective ends of the cartridge fuse, the block being provided with slot means for slidably receiving a strip or printed circuit fuse element, and portions of the contacts being exposed within the slot means for frictionally engaging a surface of the strip or printed circuit fuse element.

2. A fuse connector as claimed in claim 1, in which the portions of the contacts within the slot means are arranged to urge the strip or printed circuit fuse element against an opposite side of the slot means.

3. A fuse connector as claimed in claim 1, in which the block has a plurality of cavities arranged side by side for receiving respective cartridge fuses, said slot means defining a slot extending through the block and communicating with all of the cavities, portions of the contacts associated with each of the cavities being exposed within the slot for frictionally engaging a surface of a printed circuit card in the slot.

4. A fuse connector as claimed in claim 3, in which at each cavity there is a further slot for receiving a strip or printed circuit fuse element, portions of the contacts associated with the cavity being exposed within the slot for frictionally engaging a surface of the strip or printed circuit fuse element.

5. A fuse connector as claimed in claim 4, in which each contact has a receptacle portion of channel form arranged to grip the end of a cartridge fuse between sides of the channel, free edges of the channel being turned out to define bearing surfaces projecting into the further slot, and the base of the channel being formed with a rib projecting into the slot which communicates with all of the cavities.

6. A fuse connector as claimed in claim 1, in which each contact is mounted in a respective passageway communicating with the cavity, the passageway being of generally H shape configuration.

7. A fuse connector comprising a block of dielectric material having at least one cavity therein for receiving a cartridge fuse therein, electrical contact means disposed in said block and having receptacle sections positioned in said cavity for electrical engagement with end caps of said cartridge fuse and conductor-engaging sections extending outwardly from said block for electrical engagement with conductor means, said block provided with slot means in communication with said cavity for receiving printed circuit fuse means therein for electrical engagement with said electrical contact means.

References Cited UNITED STATES PATENTS 2,934,627 4/1960 Bristol et al. 337-293 2,941,059 6/1960 Sims et a1 337-187 3,116,386 12/1963 Sperzel 337-188 3,281,555 10/1966 Fister 337-188 BERNARD A. GILHEANY, Primary Examiner H. B. GILSON, Assistant Examiner US. Cl. X.R. 337-487, 227 

